Assigning text for a textbox when the selecting a value from dropdown

Question

I want to change the text of a textbox based on the value selected in the dropdown. This is the code i wrote

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
    int a = 2;
    int b = 3;


    if (DropDownList1.SelectedValue == "Manager")

        TextBox7.Text = Convert.ToString(a);

    else if (DropDownList1.SelectedValue == "Front office")
        TextBox7.Text = Convert.ToString(b);

}

When i select the value from the drop down the value doesn't change in the text box.

Any help will be appreciated.

Answer 1

You need to make sure you set "AutoPostBack" to true on your DropDownList.

<asp:DropDownList = runat="server" ID= "DropDownList1" AutoPostBack="True">
</asp:DropDownList>

Unlike with desktop applications, the code you write in your event handlers won't fire until the aspx page posts back to the server (refreshes).